Catalyst composition for polymerization of olefins

A process for preparing a catalyst composition, comprising contacting a magnesium-containing support with a halogen-containing titanium compound, a monoester, a first internal electron donor represented by formula (I), and optionally a second internal electron donor selected from a group consisting of diesters and diethers,

• wherein:
• R1, R2, R3, R4, R5 and R6 are the same or different and are independently selected from the group consisting of hydrogen, straight, branched and cyclic alkyl having at most 20 carbon atoms and aromatic substituted and unsubstituted hydrocarbyl having 6 to 20 carbon atoms;
• R7 is selected from the group consisting of straight, branched and cyclic alkyl having at most 20 carbon atoms and aromatic substituted and unsubstituted hydrocarbyl having 6 to 20 carbon atoms;
• and
• R8 is selected from the group consisting of aromatic substituted and unsubstituted hydrocarbyl having 6 to 20 carbon atoms.

A catalyst composition for the polymerization of olefins, comprising

• an acetate or benzoate monoester;
• a compound represented by formula (I) as a first internal electron donor
• wherein:
• R1, R2, R3, R4, R5 and R6 are the same or different and are independently selected from the group consisting of hydrogen, methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, phenyl, trifluoromethyl and halophenyl,
• R7 is selected from the group consisting of methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, phenyl, benzyl, substituted benzyl and halophenyl, and
• R8 is selected from the group consisting of substituted or unsubstituted phenyl, benzyl, naphthyl, ortho-tolyl, para-tolyl or anisol;
• a magnesium-containing support;
• a halogen-containing titanium compound;
• and
• optionally a second internal electron donor selected from a group consisting of diesters and diethers.